A 23-year-old faces murder charges after Houston police say she stabbed her boyfriend to death because he planned to leave her.

Lauren Callis had a different story for Houston police officers that arrived on the scene on July 21 at 100010 Cullen, where her boyfriend Demarcus West suffered a fatal stab wound to the chest, according to a court document from Harris County District Court.

Callis told investigators that she and West had been dating for 4 years and had a child together. She said that evening at about 2 a.m. she came home from a nightclub to their apartment on Cullen and they began fighting because he was angry she stayed out so late, she initially told investigators.

Callis said he threw her to the ground of their bedroom, jumped on top of her and began to choke her by pushing his knee into her neck and throat. She told investigators she was able to push him off her and she ran to the kitchen to get a knife for protection.

West asked her, "Are you going to stab me?" before she thrust the knife only one time into his chest, she said. She said she called 911 as he stumbled and fell in the hallway and she attempted to give him CPR. West was taken to Ben Taub hospital, where he was pronounced dead.

Upon further investigation, Houston police officers began to suspect her version of the story.

The officer that arrived on the scene noticed a purse near the door of the apartment and noted that she could have run from the apartment easily, without returning to West with a knife. He also noticed that she did not have any injuries that lined up with her story that he attempted to choke or restrain her. He also discovered that her claim that she had called Houston police on West many times before was untrue.

He instead found calls in which West had called the police for service because of Callis' violence toward him, the document states. The 911 call placed the evening of West's death did not indicate that she had performed CPR on her boyfriend. The officer said he could hear her yelling "Get up!"

Another woman, who had been dating West at the same time, said that he had told her the night he was killed that he was planning to break up with Callis. West's sister and mother told police they had seen Callis act physically aggressive toward West because she was jealous of other women, the document states.

Investigators interviewed several of West's former girlfriends, who all said that he was never abusive and typically avoided confrontation. One described him as "a lover not a fighter."

An autopsy report showed wounds in the left arm, the back of the neck and a fatal wound in the chest, which also did not line up with Callis' story that she stabbed West once.